山西大学学生身体素质状况的跟踪研究

该文通过对山西大学在校学生 1992～ 1999年的素质状况的跟踪研究 ,针对显示出的问题提出相应对策 ,为改善大学生的身体素质提供科学依据     

A regression-based smoothing spline Monte Carlo algorithm for pricing American options in discrete time

American options in discrete time can be priced by solving optimal stopping problems. This can be done by computing so-called continuation values, which we represent as regression functions defined recursively by using the continuation values of the next time step. We use Monte Carlo to generate data, and then we apply smoothing spline regression estimates to estimate the continuation values from these data. All parameters of the estimate are chosen data dependent. We present results concerning consistency and the estimates’ rate of convergence.     

When the Export of Social Problems Is No Longer Possible: Immigration Policies and Unemployment in Switzerland

Throughout the twentieth century, Switzerland has been one of the OECD countries with the highest proportion of immigrants in its population. The aim of this article is to show how institutional factors have shaped the opportunities for change in immigration and immigrant‐employment‐related policies there in the 1990s. Whereas unemployment had remained low in the 1970s and 1980s, there was a marked increase at the beginning of the 1990s. Existing migration policies were considered a central cause of this increase, since the great majority of foreigners who had come and settled in Switzerland in the periods of economic expansion were low‐skilled, and were now over‐represented among the unemployed. The reforms undertaken in the field of immigration and integration policy to respond to these new problems have been determined by specific institutional factors: direct democracy, a defensive migration regime, the development of immigrant rights and the weak autonomy of the central state. These factors account to a large extent for the limited scope and specific pathways of policy reforms in these two domains.     

Incomes after Job‐loss in the United States: From Programme Rules to Panel Data

Welfare state studies are usually motivated by one or both of two concerns: programme effects on the incidence of poverty, and the possibility of perverse incentive effects. Most research has been comparative, using cross‐national indicators from the Organisation for Economic Co‐operation and Development and other international organizations. That research often contrasts the generosity of programmes in a number of European countries and the lack of it in the USA. Focusing on income transfers after job‐loss, in this article we critically examine the comparative evidence on US welfare state generosity and then use the Panel Study of Income Dynamics (PSID) to estimate what happens to job‐losers' incomes. The comparative analysis suggests conclusions more nuanced than found in much of the literature. The PSID analysis shows how the income effects of job‐loss vary across job‐losers and suggests that the role of unemployment compensation programmes in supporting incomes may be overstated.     

Unemployment and men's entrance into female-dominated jobs

Despite the contraction of many male-dominated occupations, men have made limited progress in entering female-dominated jobs. Using monthly employment histories from the SIPP, we examine whether individual economic conditions—such as a period of unemployment—are associated with men subsequently pursuing female-dominated work. Specifically, we ask whether men are more likely to enter female-dominated jobs after unemployment, compared to men who take a new job directly from employment. We find that unemployment significantly increases the odds of men entering female-dominated work among men who make job transitions. By examining changes in occupational prestige as well as wage differences before and after unemployment, we also find that entering a female-dominated job (compared to other job types) may help men mitigate common scarring effects of unemployment such as wage losses and occupational prestige downgrades. Accordingly, this study reveals a critical occupational route that may allow men to remain upwardly mobile after involuntary unemployment.     

The role of social capital in the job-related regional mobility decisions of unemployed individuals

Social capital is an important factor in interregional mobility. Although most prior research has focused on its role in the job-finding process, this study investigates the function of social networks and the social capital embedded therein after an interregional job offer has been received. This subject is particularly important for the unemployed, who should be able to exploit a mobility strategy to re-enter the labour market. Unemployed persons rely on their social networks to cope with joblessness, but there is evidence that social contexts can also act as mobility traps for this group (Windzio, 2004). We examine whether the unemployed weight social capital in a unique manner when making decisions regarding mobility.To investigate these issues, we combine a factorial survey module (FSM) with data from the German “Labour market and social security” (PASS) panel study to generate representative samples of both unemployed and employed persons with a randomised mobility stimulus in the form of hypothetical interregional job offers. Our results reveal the mobilising effects of exposure to conflict-laden relationships with the social network and the household. These are particularly pronounced for unemployed persons, highlighting the importance of factors that influence decision making about mobility beyond simple economic considerations.     

A multiple warm standby δ-shock system with a repairman having multiple vacations

In this article, a warm standby n-unit system is studied. The system is operational as long as there is one unit normal. The unit online, which has a lifetime distribution governed by a phase-type distribution, is also attacked by a shock from some external causes. Assume that shocks arrive according to a Poisson process. Whenever an interarrival time of shock is less than a threshold, the unit online fails. The lifetimes of the units in warm standby is exponentially distributed. A repairman who can take multiple vacations repairs the failed units based on the “first-in-first-out” rule. The repair times and the vacation times of repairman are governed by different phase-type distributions. For this system, the Markov process governing the system is constructed. The system is studied in a transient and stationary regime; the availability, the reliability, the rates of occurrence of the different types of failures, and the working probability of the repairman are calculated. A numerical application is performed to illustrate the calculations.     

Psychologically and biochemically assessed stress in a follow-up study of long-term unemployed

Abstract

It has been suggested that psychological stress is one of the reasons for the high morbidity among unemployed people in Western countries. The same may apply to the well-documented high mortality. It would be expected that increased levels of biological stress would be found in these people. In the present study a sample of 310 long-term unemployed people from Norway was followed for 2 years. Psychologcal stress was assessed by medical examination and by the psychometric tests GHQ-28 and HSCL-30, the latter compared with a reference population of employed people. Serum levels of cortisol, prolactin and testosterone, together with immunoglobulins IgA, IgG and IgM, were compared with working controls. The unemployed had a high level of psychological distress at the first examination, the sanie for men and women. At the 2-year follow up distress was reduced by re-employment. This fits the ‘causation hypothesis' which explains the high distress level as caused by unemployment. The other direction of causation, ‘the selection hypothesis', assuming that distressed persons have an increased chance of continuous unemployment, was also confirmed in the present study. As for biological stress, significant differences were not found between the unemployment, the re-employed and the working controls.     

Working to get fired? Unemployment benefits and employment duration

In many countries, jobseekers are entitled to unemployment benefits (UBs) only if they have previously worked a minimum period of time. This institutional feature creates a sharp change in the disutility from unemployment at UB eligibility and may distort the duration of jobs. In this paper, we evaluate this eligibility effect using a regression discontinuity approach. Our evidence is based on longitudinal social security data from Portugal, where jobseekers are required to work a relatively long period to collect UBs. We find that monthly transitions from employment to unemployment increase by 10% as soon as the eligibility condition is met. This result is driven entirely by transitions to subsidised unemployment, which increase by 20%, as non-subsidised unemployment is not affected. The effects are even larger for the unemployed with high UB replacement ratios or those who meet the eligibility condition from multiple short employment spells. These transitions deserve greater attention from UB agencies and public employment services.     

Geographic labour mobility and unemployment insurance in Europe

Conventional wisdom suggests that the generous provision of UI in Europe can account for the low regional mobility rates. Emphasizing the disincentive effect, this hypothesis ignores that UI might also have a positive effect by relaxing liquidity constraints in the presence of mobility and search costs. This paper investigates empirically the effect of UI on geographic labour mobility for five European countries. Overall, the findings suggest that receiving benefits is not associated with lower mobility, and they indicate that the effects might vary depending on the institutional characteristics and the incentive structure of the UI system of each country.